PRISMATIC SECONDARY BATTERY EMPLOYED WITH SAFETY PLATE

摘要

The present invention provides a prismatic secondary battery in which an electrode assembly including an anode, a cathode, and an isolation layer is sealed in a prismatic battery case. The battery case includes a rectangular case body having an open top end and formed by a metal material, and a case cap coupled with the open top end of the case body and including an electrode terminal. A safety plate broken upon generation of high pressure inside a battery is formed on the case body. The safety plate includes a linear notch groove crossing a vertical center axis at both surfaces of the case body, and left portion and right portion of the notch groove are asymmetric to each other based on a vertical center axis of the case body. A remaining thickness of the vertical center axis in the notch groove (thickness obtained by subtracting a depth of the notch groove from a thickness of the case body) has the smallest value.